Electrified vehicles, such as hybrid electric vehicles (HEV's), plug-in hybrid electric vehicles (PHEV's), battery electric vehicles (BEV's), or fuel cell vehicles differ from conventional motor vehicles because they are powered by electric machines (i.e., electric motors and/or generators) instead of or in addition to an internal combustion engine. High voltage current for powering these types of electric machines is typically supplied by one or more high voltage battery assemblies.
Some electrified vehicles are equipped with a climate control system that employs a heat pump subsystem for warming, cooling and/or dehumidifying a passenger cabin. For example, the heat pump subsystem can be operated in a heating mode in which the passenger cabin is heated, a cooling mode in which the passenger cabin is cooled, and a dehumidification mode in which a vehicle windshield defrost function is supported. It is desirable to improve operation of the climate control system during certain conditions.